I just tagged v11 of the python btrfs library.
https://github.com/knorrie/python-btrfs/
Here's the summary of changes (from CHANGES):
python-btrfs v11, Feb 28, 2019
* Promote some useful examples to proper programs, and add a man
page for them. Distro package maintainers can ship these in
/usr/bin.
- btrfs-usage-report
- btrfs-balance-least-used
- btrfs-space-calculator
- btrfs-orphan-cleaner-progress
* Add TEMPORARY_ITEM_KEY and PERSISTENT_ITEM_KEY, which have replaced
BALANCE_ITEM_KEY and DEV_STATS_KEY in kernel code a while ago.
* Various small documentation and bug fixes.
Hans
